Of the Kuril Seal, Sapporo, 1985 (Summaries)
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哺 動 学 誌(J. Mamm. Soc. Japan) 11(3•E4): 127-146 December 1986 Proceedings of a Symposium on Ecology and Protection of the Kuril Seal, Sapporo, 1985 (Summaries) The Organizing Committee of the Kuril Seal Symposium (Representative : Kazuo WADA Primate Research Institute, Kyoto University, Inuyama 484, Japan) 1) On the Symposium on Ecology and Protection of the Kuril Seal In order to summarize the researches and protection movements of the Kuril seal (Phoca vitulina stejnegeri) in Japan during these twelve years and to create a further step in their progress, a symposium was held under the joint auspices of the Marine Mammal Research Group of Mammal Research Association, the Kuril Seal Research Group, the Research Institute of North Pacific Fisheries of Hokkaido University and the Mammalogical Society of Japan, at the Northern Region Center, Sapporo, on 10-12 July 1985. The symposium was indebted to the support and collaboration of the following organiza- tions, and many individuals. The committee of the symposium wish to express their sincere appreciation of their favors. The Nippon Life Insurance Foundation, the Northern Regions Foundation, the Northern Region Center, the World Wildlife Fund Japan, the Japanese Association of Zoological Gardens and Aquariums, the Nature Conservation Society of Hokkaido, the Hokkaido Shimbun Press, the Hokusui Society, the Hokuren Federation of Agricultural Cooperatives, the Hokkaido Gas Comany Limited, the Kamori Kankou Corporation, the Seibu Construction Company Limited, the Editorial Office of Anima (Magazine of Natural History) of Heibonsha Joint-Stock Company and the Editorial Office of Newton (Graphic Science Magazine) of Kyoikusha Joint-Stock Company. On the five subjects 25 lectures, including those by three famous scientists invited from the United Kingdom and United States of America, were addressed to an audience of about a hundred, and there was eager discussion on each lecture throughout the three days. On the third day, an appeal for protection of the Kuril seal was adopted at the general discussion unanimously, after a heated debate including speeches by fishermen engaged in salmon trap net fishing. We hope to keep a record of the symposium ; summaries of lectures and the •gSapporo Appeal•h. We are much obliged to the Editorial Committee of the Mammalogical Society of Japan for their giving us an approval to publish the record in the journal of the society. And we express our heartfelt gratitude to Mr. W. N. Bonner, British Antarctic Survey, Natural Environmental Research Council and Mr. S. Azuma, Primate Research Institute, Kyoto University for their revising the manuscripts with great care. Along with the symposium, the following four events were held ; a photoexhibition introducing the Kuril seals (on the theme of •gCorrespondence from the Rough Reefs•h, on 8th-12th at Aurora Plaza, an underground plaza in Sapporo) ; a night session (on the theme of •g Fauna in the Shiretoko Peninsula•h, •gMain Breeding Grounds of the Kuril Seal•h, •gDiving Depth of the Northern Elephant Seal•h and •gGeographical Variation of the Pelage Pattern of the Kuril Seals along the Northern Pacific Coast•h, on 10th at the Faculty of Agriculture of Hokkaido University) ; a public lecture with a documentary film (on the theme of •gThe Seals 128 Symposium on the Kuril Seal on our Northern Shores•h, on 13th at the Kita-ichijo Assembly Hall of the Hokkaido Shimbun Press), and an excursion for one of the habitats of the Kuril seals (on 13-15th. The destination was Gome-iwa Rocks, a breeding ground of the seal on the shore of Hamanaka-cho, Kushiro). An additional note : We plan to publish a book entitled •gEcology and Protection of the Kuril Seals•h, sponsored by the Nippon Life Insurance Foundation, from the Tokai University Press in November, 1986. (Tetsuro IToo) 2) Summaries of lectures a : The aim and present status of the Kuril seal protection movement The object of the Kuril seal symposium Kazuo WADA Primate Research Institute, Kyoto University, Inuyama 484, Japan The object of the present symposium shall be to create a concrete and effective counter- plan, at present and in the future, for Kuril seal protection. Upholding a designation of the seals as a precious natural product for their protection, we have carried out for a little over ten years many investigations to make clear the biological characteristics of the seals and actual condition of seal damage to coastal fisheries. We hope to discuss thoroughly, based on the substance of these investigations, the following themes : biological characteristics of the seals on the first day, seal damage to the fisheries and research conducted in the United Kingdom and the United States of America on the second day, and the relationships between seals and fisheries from historical, administrative and legal points of view on the third. It is worth special mention that persons interested in fisheries are asked to be present at the conference. In the past, conferences of this kind used to be held with attendance from the protection side only, but at this time we expect straightforward discussion from fishermen concerning actual damage by seals. It is a great pleasure for us to have three famous research workers from two foreign countries at the conference, and we expect them to furnish material rich in content. Also we hope they will give us frank comments and advice from the viewpoint of countries having not only more abundant experience in research and citizen movements, but also more advanced systems of legislation and administration of the seals. If a consensus of opinions are attained among the participants through discussions from many-sided points of view concerning the abovementioned problems on the last day, it would assist greatly the persons participating, at present and in the future, in research and protection movement of the seals. Our investigations and research on the Kuril seals up to now, and the conference are indebted to the support and collaboration of many organizations and individuals. On behalf of the committee of the conference, I wish to express our sincere appreciation for their kind assistance. b : Biology of Kuril seal Present status of Japanese pinnipeds Tetsuro IToo First Department of Oral Anatomy, School of Dentistry, Asahi University, Gifu 501-02, Japan Symposium on the Kuril Seal 129 A general view on the present status of eight Japanese pinnipeds is as follows : Popula- tion size of the northern fur seal (Callorhinus ursinus) is estimated at 1.765 million animals throught the world. They are pelagic and stay along the coast of Sanriku from January to April, and from May to July leave the waters of the western coast for the northern Pacific. A separate stock of the seals migrates to the Sea of Japan until June. Along the coast of the Sea of Japan satisfactory information about their migration has not yet been gathered. In Asian waters the Steller sea lion (Eumetopias jubatus) breeds on the Kuril Islands and on islands in the Okhotsk Sea. Their total population is estimated at about 6,000 animals. The sea lions come down to the coast of Hokkaido and stay there during winter and spring. Some groups of them occur along the coast of nothern Hokkaido (ca. 1,000 individ.) and another herd, 3,000-5,000 in maximum number, migrates to Nemuro Strait. In recent years the number of animals, range of migration routes and number of haul out rocks have greatly decreased throughout the areas. There are no records of the Japanese sea lion (Zalophus californianus) through the last 40 years ; they have already been exterminated in Japanese waters. Four phocid seals occur in Japan in addition to the Kuril seal (Phoca vitulina stejnegeri) ; these are the larga seal (P. largha), the ribbon seal (P. fasciata), the ringed seal (P. hispida) and the bearded seal (Erignathus barbatus). Population sizes of the first three in the Okhotsk Sea are estimated at 168,000, 140,000 and 800,000-1,000,000animals, respectively. That of bearded seal in the north Pacific is 450,000 animals. These pagophilic seals migrate to the waters off Abashiri and the Nemuro Strait during the season of drift ice, but their number has not yet been surveyed. Some hunting records show that 1,500-10,000 seals were captured annually during 1968-1976 in the waters off Abashiri, including the coastal waters of Skhalin, and about 1,000 seals were captured in the Nemuro Strait. The larga and ribbon seals account for about 90 per cent of all harvest in both areas. After the drift ice season, only a small number of larga seals remain sedentary along the coast of the Okhotsk Sea and the Nemuro Strait. In recent years the numbers of these seals and their haul out sites have been greatly reduced. The number of Kuril seals in the Kuril Islands is estimated at about 2,400 animals. In Hokkaido they occur only along the rocky shores of the Pacific coast of eastern part of the island, where they are sedentary all the year round without association with drift ice. The population size and number of haul out (breeding) sites have been reduced by hunting and other causes during the last twenty years, and only 300-350 seals survive in Hokkaido at present. It is concluded that reduction and extermination of coastal pinnipeds has progressed northwards, from Honshu to Hokkaido in the Japanese Islands. Summary of the Kuril seal census during the past twelve years Takeshi SHUKUNOBEObihiro University of Agriculture and Veterinary Medicine, Obihiro 080, Japan and Tetsuro IToo First Department of Oral Anatomy, School of Dentistry, Asahi University, Gifu 501-02, Japan After the warning by the Marine Mammal Research Group in 1973 that the Kuril seal (Phoca vitulina stejnegeri) in Japan was at a crisis of extermination, sixteen censuses were taken to learn the number and status of the seals.